Pipe wrapping and method and apparatus for applying same



June s, 194,5.

PIPE WRAPPING AND` METHODNAND APPARATUS F4011 APPLYING SAME Filed June- 4, 194s 2 sheets-sheet 1 J A x A l uw, um, @l

`IMAVHMHHLI JAY Zeni?? Zronaozb.

D. BRoNsoN 2,377,608

PIPE WRAPPING AND METHOD AND APPARATUS FOR APPLYING SAME v June 5, 1945.

Filed June4, 194s l 2 sheets-sheet 2 EINE HWF Y I H ...NMI

VPatented June 5, 1945 h PIPE WRAPPING AND METHOD l AND APPARATUS FR APPLYING SAME Deming Bronson, Cleveland, Ohio, assignor to `General Paint Corporation,

Calif., a corporation of Nevada San` Francisco,

Application June 4, 1943, Serial No.`489`,684

19 Claims. e (Cl. 242-11) 'I 'he invention relates generally to the art of wrapping pipe and primarily seeks to provide certain new and useful improvements in a protective wrapping for pipe or the like and a novel method of and apparatus for applying said wrapping.`

In" the preparation of certain forms of pipe for the market, especially those intended to be buried in the ground to serve as water or like conduits, it is customary to apply to the internal surfaces of the pipe a bitumen coating having the quality of preventing tubercle formation, and a protective covering also is applied over the external surfaces of thepipe usually comprising a bitumen or other plastic protective coating, a spirally wound layer of relatively heavy felt and an outer layer of kraft paper also spirallywollnd. The adjacent edges of the 4spirally wound webs or strips of felt and paper are overlapped so as ence than does the main body of the web and p obviously a considerable amount of tension is e established in theoverlapped edge portion. This greater tension in the overlapped edge portion as compared to the other edge portion of the web Visja pressure force that isexerted'inwardly towardthe covered pipe, and when the wrapping is applied over a plastic coating, the inward pressure at thespiral line underthe overlapped web 'margin has a tendency to displace the plastic coating entirely or at least to reduce its thickness undesirably. This displacement or compacting and thinning of the plastic protective coating obviously is objectionable because it weakens the coating just where infiltration from without is most likely to occur, namelyjat` the spiral line alongwhichthe web lap lies, and it 'is a purposeof the present invention to provide a method and means for preventing thisreduction or destruction of the efficiency` of the protective coating. h h

In its more detailed nature `the invention has for an object to provide a novel protective wrapper web having a marginal edger thereof so prepared by punching, slotting, slitting or otherwise asto be free to expand or increase in diameter as it is being wound in edge overlapping relationso as to avoid establishment of edge tension effective to press inwardly on and displace or k objectionably compact the 4underlying plastic a novel apparatus for wrapping a web spirally about a pipe and including means for treating a marginal edge of the web to relieve or prevent edge tension as the web` is beingrwrapped.

Another object of theinvention is to provide a novel method of spirally` winding a protective web about a pipe with edge portions of the web overlappingand including the step of `progressively treating the edge portion of the web intended to4 overlap while the winding of theweb is in progress and for the purpose of relieving or` preventingV edge tension in the `overlapping edge portion of the web.

With the above and other objects inview that I will hereinafter appear, the nature of the 'invention willbe more fully understood by *following thedetailed description, the appended'claims l andthe several viewsillustrated `in the accom# panying drawings. l t In the drawings; i `Figure lis a somewhat diagrammatic plan view illustrating' the invention.

A Figure 2 is a detail fragmentary plan. view ill lustrating means for treating the felt web edge portion.`

Figure `3 is a detail vertical cross sectionrtaken y on the line 34-3jonFigure2. e Figure 4 is a detail fragmentary vertical longitudinal section taken on the line d--ll on Figure2. f i Figure 5 is a View similar to Figure 4 illustrating a modified form of edge treating means.

Figure 6 is a fragmentary plan view illustratl ing a fragment of felt web"treated in the manner illustrated in Figure 5.A

FigureY 'I is a view similar to Figure 6 illusof treating a felt `web edge portion.

trating a modied manner Figure s is a View similar to Figure 5 mostrat- `ing another modified means for treating a web `with the present invention, a web edge treated in the manner illustrated in Figures land 2 being shown.

Figurellis a view similar to Figure 15, a web edge treated in the'manner illustrated in Figure Sbeing shown.

In the example of embodiment of the invention herein disclosed, the invention is illustrated as being practiced in a wrapping machineof a type well known in. the art and .disclosedin detail in U.'S. Letters Patent `l:,5'72,258tissue'd to Wieland'etl al. on'Fbruary 9, "1926,lthough it is t be understood that the invention can be practiced as well in any form apparatus.

- In the machine referred to'tlrereilisiiniutlelita framing whereon is suppDrted a 'turntablej which is adjustable about a :vertical axis. 0n the turn table there is mountedv a`pairo`f .angularly disposed, power driven. rolls 1 on which'the pipe 8 which is to be externally .coa'teiisand wrapped rests and by which said pipe. is given rotative and longitudinal movement. Therlls f1 are driven :ifrom the motor z *g'enerally edesignatedrS.

:feltf stand @.:or frame 'f HJ: is provided :and von this stand :thef supplyrroll t I cof eltvis tim-curated. .Thei felt .-wrappingswebi isvwrappedz Labout .thegpipe @81 in f thermann-er --clearly illustrated .zin @Figure r.1

and .the 'rotating ;pipe :ser-Ves to .#.dtaw the .-Web |12 .off :of the supply rol1 1 ljl *.the, positioning cof .the pipe-'supportingranda-driving rolls :Ts-andtthe yangular 'relation :of tl1e5feltf stand filsbeirrg :uso -relatejdvas toucause l. thelfweb l2 .-tofwrape-spirally "ab'outfthapipefsatY the; properfangle'-andvwthf one edge portion of the web.-overlappingmstindicated .ullccording to standard practice in theg protective twrapping .of i pipe, ia hot '.bitum'en coating :is applied :externally t to the gpipe, ifa :felt :web :is wrapped;spirally-abouttherpipe over. `thenbituznen coating, and then the outerccovering of ekraft paper is wrapped spirally aboutttheJp-pe :over the. felt' wrapping, wsfith .or-withoutuan additi'onal protective coating of hotbitu-men interveningthe .felt-.and 1.papera mappings. The Thot .bitumenpproftective .-.coating may tbe .applied rto the pipe sso as to underlie the felt wrapping inany approved mannen-iias.by.directidepositionontotheeexternal surface of the rotating-.andsiongitudinally moving .pipe by fdra'gging'fagrannymag having hot=.bitu men dep'ostedfthereon.- against theamovingpipe,

or by direct deposition of the hot bitumen through .a ydistrtbutor pipe `I 4 r or -.other applicator :onto the upper.- surface f. of i the .telt/Web I2 ...opposing the `externalzfsurface of z the .pipe in ether manner indicatedat t5. in Figure 1.

A kraft paper stand entraine liisiprovided .andssupportszgiasupply l.roll .VI .from .which zthe ent invention except in .combination `with the structureslandpractioeswhich.are to be described .detaithereinaften .Thevhereinabove described 'fconventional structures rand :practices .fare .dis-

rclosed inodetail-.in ,;U. :S5-.Letters :Pa-tent 1,572,258 issued to C. F. Wieland et a1. on February e9,

1926, and in U. S. Letters Patent 2,133,014 issued i to David W. Boylan on October 28, 1936.

According to the present invention .the felt web I2 while passing to the pipe and being Aspirally of spiral wrapping' Wrapped thereon goes through an edge treating means generally designated I9 in Figure 1. The

edge treating .means maytake variousforms, andV u cork :ortotlfrerf` suitable material into which thev slitting blades 2l can bite. See Figures l and 4. Thetrllsranld'are fixed on shafts 23 which ."are4 rotatableiinzupper and lower bearing blocks 2'lit'i1tably mounted at 25 in bearings 2t. A com- .pressionsspring 1:21. preferably is interposed .be-

tweenthe outer portions of the tiltably mounted blockszllrso as to urge the opposing rolls 20 and '2v2 together.-against-.the interposed w.ebTedgegportion, said rolls including i friction @ring .portions .28 @which engage ..the web v.1.2 l.vso :as to causetthe iineai-.movementiof theswebtobe transmittedin the. norm-0f rotation-to theerollszu .and\.22. :One of the rolls is equipped with an edge guide flange Spend the,rolls..also are-.equipped ,withfinter- .meshing agears .[30 .which :.cause them u.--to rotate Atogetlaergin a ...manner assuring c.against `tearing consisting .of the .provision ...of-1a. multiplicity of :equidistantly placed.- apertures,:.arranged.in;.a..line -spacedtinwardlyfromiancedge of fthe .Wenn-.distance.. approximating .theidegreeto which... the. .edge portiomof t,the web :is '5to .overlapatheuwebxwrapping. .One l`wayf performing ...this type of :web edge-,treatmentis. by,provision -of ,..opposngerols having.icompleznentarymmches' 3 l and. receiving.

.recesses 3 2 in ...the manner clearly` illustrated .in Figure 5 :rand whichserve .to rprovide .the .linetof apertures.`33. in `,the.webL11-M.illustrated .in Figures 5.an'dl6. n A

AIn. Figure f7 '.there. isillustnated; anothenmodiii- .cation ..0f ledge .treatment .of the felt web, Vthis treatment.. consisting of a combination changularlydisposededge ;slits`.35, the slitslbeing. directed rearwardly and laterally Withrespect tothe direction f .feed ,of `the web lv 3B as. indicated ,.by;. .the arrow .3.1, iand. .each `slit .terminating at its. inner .extremity in ...an aperture ..38. The y.provision .of thaapertures willlovercome :any ..tendency..o`f .theffslits ..to..tear attheir. innert extremities, .and

.byianglingthe slitsin the manner.stated,.. upfold.

ing. olflthetriangular web edgeportions formedrby the. ,provisionl..of .the ..slits. is avoided .during .the

wrapping. ofthe .webpnto the .p.ip,..and, instead, theweb.; edgerportions' interveningthe. .slits .3 5. .are caused to `tightlyhugthe overlapped .webedge Aportions and lie. ilatly against :the yiin'derlying wrappingiso.-thatlin..the;nished product-namely theccompletelyrwrappedpipathe very presencebf the'slits ,can be.observed.only withidifculty.

L'Injl'iguresll Uand $9 .of ,.theidrawings, ,therelis 'illustratedestill.another .mannersof ...treating the edge,.portion ;6f..the.lfe1t ,.web. ...According ,tozthis modication.pt theinventon; the .edgeportionfpf 4the..\vveb.1i$i. .maybe crimpedeas. .at llllsbetweennpposing crimping rolls 4l. i y -..In-.Eigurev.l0.ot:the drawings thereis illustrated still another modied form or web edge treati i In Figure 12 of the drawings there is illustrated i still another modification of web edge treatment in which equidistantly spaced edge slotsv4'l are provided, alternate ones of the slots merging into apertures or slots 48.

In Figure 13 of the drawings there is illus- CJI.

trated still another modified form of web edge y treatment in which the web edge is provided with equidistantly spaced transverseslots 49 without intervening apertures or. slots.

In all of the forms of web `edge `treatment illustrated in the variousFigures 1, 2, 6, '7, 9 and10 to 13 suiicient yield, or freedom to spread is provided at the edge portionof the web which is intended to overlap an underlying web edge portion to` enable the desired overlapping without storing of objectionable tension in the overlapping edge portion rwhich `must pass around a greater circumference than the underlying, main body portion of the felt wrapping web. It will be appreciated that because of the considerable thickness of the felt wrapping web i2, the amount of` tension that can be stored up in an overlapping edge portion thereof is considerable, and the objectionable nature of the inward pressureresulting from this storing up of tension can be best appreciated by observing Figure 14 of the drawings in which the conventional practice of wrappingis somewhat diagrammatically illustrated.

In Figure 14 of the drawings the pipe `being wrapped is indicated at 50and the external protective coating of hot bitumenis indicated at 5I. The felt web wrapping is indicated at 52 and the overlapping edge portion of the wrapping is indicated at 53.-` Because of the tension stored up in the overlapped edge portion 53 as it passes around the external surface of 'the underlying web portion, and the inward pressure resulting from this tension, the plastic coating `5| isidisplaced or pressed inwardlyas at 54 in a manner resulting in `complete destruction of, or at least great reduction in, the efliciency of the hot biturnen coating at the spiral line of the web overlap. `It is the purpose of the present invention to provide means overcoming this objectionable storing up of edge tension and plastic coating displacing-inward pressure. i

By providing the web edge treatments hereinbefore described, the overlapping edge portion of the felt web ispermitted to spread and relieve the edge tension and inward pressure as the web overlaps in the manner clearly illustrated in Figure 15, and displacement or reduction in efciency of the hot bitumen pipe coating is avoided. In

Figure 15the pipe is indicated at 55, the hot bitui men external coating at 56, and the felt web is indicated at 58, and the freeing of the web edge portion by reason of the provision of this edge A slitting or slottingpermits the web to overlap at 59 without any objectionable storing of edge tension therein or the setting up of inwardly directed'pressures against the underlying plastic coating 56, with the result that the plastic `coating remainsintact and in` fully efficient full 'thickness as at 60 along the spiral'line underlying the Voverlapped edge portions of the web wrapping '51. It should be understood that all of the forms of web edge treatments illustrated in Figures 1, 6, 7, 9 and 10 to 13 will provide suflicient edge freedom to avoid the setting up of objectionable edge tension in the web in a manner for avoiding the objectionable displacement of the plastic coating indicated at 54 in Figure 14. 1 i

In Figure 16 `of the drawings there is illustrated a form of web edge treatment such as is illustrated in Figures 6,` 10 and 11 in whichapertures are providedat equidistantly spaced points along the edge portion of the web. In said Figure 16 the pipe is indicated at 6 I, the hot bitumen coating at 62, and the felt wrapping at 63. lThe edge treatment consisting of or including the apertures or slots is indicated at 64 and an overlapped edge portion of the web 63 is indicated at 65. It will be observed that the edgey treatment ,proe vides suiicient freedom to avoid storing up of edge tension and inward pressuressuch as would displace or thin-out the plastic protective coating at 66, and it will be observed also that the plastic coating keys into the web edge treatment openings 64 in the manner indicated at 6T, a feature which contributes toward perfectv union of the wrapped assemblyand a locking together of the protective wrappings.

In the foregoing description I have disclosed several novel forms of, protective wrappings for pipe, also a novel method ofandfmeans for edge treating `the wrapping and applying the same to the pipe in a manner for assuring against the storing up of edge tension in the wrapping and the settingup of pressure forcesk effective to displace and render inefficient the plastic protective coating underlying the web wrappings.`

It is, of course,fto be understood that the details of structure and the arrangement of parts may be variously changed and modified without departing from the spirit and scope of the invention.

I claim: i

1. In apparatus of the Vcharacter* described,

pipe supporting means, means for supporting a single thickness wrapper web, means for effecting a wrapping of the web spirally about the pipe with edge portions of the web overlapping, means for performing a mechanical non-additive treat-A ment upon onlythat edge portion of the web intended to overlap thereby toenable the overlapping edge to `spread and permanently remain spreadso as tovrelieve edge tension and inward pressure where it overlaps an edge portion of the spirally Wound web.

2. In a pipe Wrapping machine, means` for rotating and feeding longitudinally .a pipe to be Wrapped, means for directing a single thickness Wrapper web in angularrelation to the pipe to f to overlap thereby to enable it to spread and perwrapping at 5T. `The web edge slitting or slotting manently remain spread so as to relieve inward pressure where it overlaps the underlying web edge portion. i

3. In a pipe wrapping machine, means for ro tating and feeding longitudinally a pipe to be wrapped, means for 'applying a plastic protective coating on the pipe, means` for directing `single thickness wrapper web f in angular relation to the pipe to be .Wrapped thereon spiraily oversaid 4:tion aof': the webmritended'nto'azoverlap thereby zito enableitto`spread1an`d assumeeandrretainithev in- .creased :diameter fresulting: from :its :overlapping of'rhet underlying web '.edgezportion l:Without :ex-

erting pressure inwardly sutlci'ent to dispiace and sappreciablya diminishrthe :.eii'ciencyroff said plasticzprotectivecoatingu l VA.1.45 Iniapparatus 4of :theicharacter described,` pipe :supporting means,A 'wrapper web :supporting means; means for efectingsfa wrapping ofxthe web spirallieyabout k.the :pipez with Ledge 'portions of the web. overlapping,candiimeansffor slittingy fan Iedge portion: of'tlie:yvebtofienable:itto "spread andre- :lieve edge tension and 'inward .pressurefas it :overlaps .aan .f'edgeiiiportion fof 'the "spirally Wound fweb.

: 5. .F.Inappairatuszof the .character described'pipe .supporting means ,fwrappenweb supporting'mea'ns, means'forseffectingv a:.wrapping of 1the Webfspirallyiabout thef piper-With 'edgefportions ofthe web .overlappingjandi' mea-ris'iorfcrin'iliingaan4 edgeA portion .oftlre web ito enable it to 'fspreadfand rerlievefe'dge tensioni-aridl inward pressure Ias it overlapsaa'n .-edgel portion of vfthe'Jspirally"Wound web.

6. In a pipe wrappingimachine, Ameans 4for rotatingzand feedingl'longitudinallyfa pipe to be :wrapped-'means vefon-applyingy a Aplastic protective :coating on the' pipe, ymeans ffor :directing-a-wrappei-#Web in angular relation to 'the pipe to yloe 'wrapped thereon'fspirally over said coating and .With,;an..edgeA portion :thereof beingiiwoun'd overlapping ,a :previously Wound edge portion, and means forstreatirigl said' overlapping edge portion to enable y iti tofspreadfand lassume the vincreased diameter zresulting *from itsoverlapping 'of the underlying 'web `edge Aportion "without exerting pressure' inwardly-:sucient '.to .displace and appreciably diminish the efficiency of saidY plastic protective coating, said last named means in cluding a pair of friction rolls between which the edge 'portion' 'being treated passes, means-for .yieldablyf'pressingf the rolls 'against the intervening 4.web edgefanded'ge indentingfmeans on at -leastione saidiroll. i i

#7. Imaipipe fWrapping'machina 'means vfor rotating and ieedin'g llongitudinally a `pipe to "be Wrapp'eimeans for# applying' a plastic protective coatingk on `theipipe,means for 'directing' a, Wrapper :weblin vangular relation `tothe pipe to be lwrapped thereonspirally over ysaid 'coating and withfanredge portion` thereofnbeing wound overlapping a previously Wound edge portion,and

` means fortreating said overlapping .edge portion to enable. it'to.' spreadtand .assume Lthe increased diameter resultingf'fromf its s overlapping of the underlying web 'edge rportionwithout exerting pressure inwardly suiiicient/"to 'displace' and appreciably 'diminish the A'eieiency 'of said `plastic protectivetcoating,.said `last named means including-a' pair :of )friction rolls fbetweenwhichthe ledge `porti'on -being :treated -passes, rneans for .yiel'dably:pressingv therolls againstthe;interven- .thevwebsisgprogressngsso'l\ asizto :enableszsaidirtreatifed;edgefporizionziasritnverlaps :the underlyingsweb Ledge :portion@,torspreadaiandiperman entiy: remain spread, thereby yto v"relieve edge tension@and iin- .iwardipressura L x9. 4:'Ihe herein described :method v:of wrapping 1 ipe--Whioh :pomprises "f wrapping 3 a single thickness :wrapper `tri/elo :spirally about the :pipe with edge `po'rtionsithereof"l overla-pping;applyingfapro` .tective' plastic 'L'coating to :tithe pipein :sa manner fior lying ;betWeen-:-the @pipe and said wrapping,

and :mechanically and rnonaadditively treating vthe ,overlapping f edgetportion :only lof said @web lWhile'theiwrappirrgfzofitheiweloiiszprogressingiso as to enable said treated edgefportionfasnitcoverlaps; the xzunderlyin'g" web :edge portion :to f lspread fand assume;y andretairr theiincreaseddiametercre- .the :web is progressing so astoltenable saiditreat'ed -eclge portion as itzpverlaps ltheznnderlyingrweb `iedge .portion vto zspreadand 'frelievexedgetension andzinvveuzdy pressure. C

v ..11."Theishereinideseribedzmethod of @Wrapping pipetwhich comprisesvvrapping a .fwrapperi-w'eb -spirallysabout thelpipezwith edgeL Vportions?thereof* overlapping; applying.aiprotective plastic coating .to 1. the pipe .inarmanner for rlying'petween the pipeiand said -wrappingpfandfedge treating'zthe overlapping r ledge portion rofsaid rwebl yby cutting through lthefsame szat Y'regu-'lar intervals While f the :WrappinglofH thewvebfis vprogressing Jso-astoenable -said treatededge portion as itpverlapsthe underlying web.`r edge portionfto=spread andfassume` the increased diameterresulting'fronrrits lover-lapping off thepunderlying :edge: portionwvithout-fexerting 'pressure' inwardlyosucient tto "displacef and= appreciably ldiminish*the eirlcien'cy "of lsaid plast-ic protectiveooating. Y i12. `A Apipe "wrapper finterided fitof'be spirally Wound about ia pipein `-edgeoverlapping'relation 'and `cornprisinga longf-Wrapper webhavingone edge thereof` cut 'through' at `regular i intervals' in 'a' jmannerfor enablingit to spread and assume the "necessary AAincrease "inl ldiameter 'of the spiral Wrapresultinglfrom itspverlapping of the 'underlying edge lportion-Y-vvithout lexerting appreciable inward pressure.

13. A pipe Wrapper intended Sto Jbe 4'-spirally wound aboutapipe inf-edge ovenappingrelation and 'oornprisingfa' longr wrapper-'web having one `edge fthereofslit througnat' regular intervalvsjin v-a manner'orfenabling it tospreadand` assumethe necessary increase indiameter'of the spiral .wrap resulting from its :overlappingof the underlying YedgepOrtiQn Without .exertingappreciable inward pressure.

14.A pipe .wrapper `.intended @to be-.spira1ly Wound .about a pipein Aedge overlapping...y relation and comprising...a,longiwrappereweb having-xine edge .thereof `.slitthrough f at ;regulanintervals.r in ,afmannen for.y enabling. it :torfispreadfzandzassume the f necessaryincreasezindiameteri of "the spiral .wrap resultingffromfits'overlapping'offthe under- -lying :edge ziporton Withoutffexerting 'appreciable .inwardzpressuref each said:slitbeingangled-later# web is to be wrapped.

15. A pipe wrapper `intended to be splrally wound about a pipe in edge overlapping relation and comprising a long wrapper` web having one edge thereof slit through at regular intervals in a3 manner for enabling it to spread and assume the necessary increase in diameter of the spiral wrap resulting: `from its overlapping of the underlying edge portion without exerting appreciable inward pressure, each said slit terminating inwardly in an aperture.

16. A pipe wrapper intended to be splrally wound about a pipe in edge overlapping relation and comprising a long wrapper web having one edge thereof cut through at regular intervals in a manner for enabling it to spread and assume the necessary increase. in diameter of the spiral wrap resulting from its overlapping of the underlying edge portion without exerting4 appreciable inward pressure, and there being an aperture disposedbetween each adjacent pair of lcuts and` aligned with the inner terminals of the cuts.

17. A pipe wrapper intended to be spirally `wound about a pipe in edge overlapping relation and comprising a long wrapper web having one edge thereof `crimped in a manner for enabling it to spread and assume the necessary increasein diameter of the spiral wrap resulting from its overlapping of the underlying edge portion without exerting appreciable inward pressure.

f 18. The herein described method of wrapping pipe which comprises cutting through oneside edge portion of a wrapper web at regular intervals throughout its length to render said edge portion less resistant to expansion, and thereafter wrapping the web spirally about a pipe with the cut edge portion overlapping a previously wound web edge portion.

19.l The herein described method of `wrapping pipe which comprises slitting one side edge por tion of a wrapping web at regular intervals throughout its length to render said edge portion less resistant to expansion, each said slit bearing C angular relation to said one side edgeportion,

-and thereafter wrapping the web spirally about a. u u pipe with the cut edge portion overlapping a previously wound web edge portion.`

`DEMINGf BRoNsoN. 

